Subsurface pump for flooding operations



May 1, 1951 J. E. GRAY ETAL SUBSURFACE PUMP FOR FLOODING OPERATIONS Filed April 5, 1949 Ground Level Wa'fer Bearing Sand l6 WA /K FIG. I

' 0H Bearing Sand lnven+ors z J. E. Gray E. A. Davenpowf- T heir A+-Forney Patented May 1, 1951 UNli'El) SUBSURFACE PUMP FOR FLOODING OPERATIONS James Earle Gray and Eldon Allen Davenport, Gentralia, llL, assignors to Shell Development Company, San Francisco, Calif., a. corporation of Delaware Application April 5, 19,49, Serial No. 85,524

1 Claim. 1

This invention relates to well apparatus for use in the secondary recovery of hydrocarbon fluid and pertains more particularly to a subsurface well pump adapted to be positioned in a well borehole for pumping fluid from an upper fluid-bearing formation into a lower hydrocarbon-bearing formation, where the well borehole passes through both formations.

Within the past years, it has become common practice in the production of hydrocarbon fluids to apply secondary recovery methods such as water flooding to an oil reservoir after it has been substantially depleted. The water introduced into the producing reservoir through an injector well cleanses the producing formation of its oil and moves the oil toward nearby producing oil wells.

The usual practice in such cases i to obtain the water for injection into the hydrocarbonbearing formation from a suitable source of supply on the surface, and to pump it through a well borehole and into said formation by a suitable pump located on the surface.

In many oil pools, water-bearingformations are existent above or below producing or oil or ga bearing formations. Water from an upper formation may be utilized in water-flooding the oil or gas formation through a common bore provided that the volume and pressure of the water are great enough. By employing this water, it

will be evident that the expense of obtaining and piping necessary water from extraneous sources may be eliminated.

While water from a water-bearing formation may be obtained in quantities sufiicient to carry out water flooding operation in a particular cation. the formation water may be under such slight pressure that it cannot be forced into an oilbearing layer unless auxiliary pressure is supplied by a suitable pumping apparatus.

It is, therefore, a primary object of the present invention to provide a pumping apparatus adapted to be positioned in a well borehole for pumping fluid through said borehole from one strata to another.

It is also an object of this invention to provide a well pump for pumping predetermined quantities of fluid from an upper water-bearing formation into a lower fluid-bearing formation through a common well borehole to drive the fluid in the lower formation toward a region from which it may be withdrawn to the surface.

A further object of this invention is to provide a well pump for pumping well fluid through a common borehole from one strata to another, said pump bein adapted to be run into a well borehole and reciprocated therein by equipment commonly used in petroleum production.

A further object of this invention is to provide a pumping apparatus of the character indicated, said apparatus being simple and sturdy in construction, and comparatively inexpensive to manufacture, install and operate.

Other objects and advantages of the invention will become apparent from the following detailed description taken with reference to the drawing, wherein:

Figure 1 is a longitudinal view, partly in crosssection of the present pumping apparatus positioned within a well borehole.

Figure 2 is a cross-sectional view taken along the line 22 in Figure 1.

A typical well installation is illustrated in Figure 1 wherein a borehole IE! is lined with a casing it closed at the top by a casing head l2. The annular space [3 between the borehole wall it and casing II is normally filled with cement, at least near the top and bottom of said casing as shown at M and I5 respectively adjacent any water-bearing formations it, as shown at ll. Suspended from slips it within said casing H is a string of pipe or tubing l9 which is closed at the top in preferably a fluid-tight manner by a suitable closure and lubricator means 20.

A sucker rod string 2! depends within said tubing string l9 and is reciprocated therein by the oscillating motion of a walking beam 22, which is driven by a pitman 23, crank 24 and prime mover 25.

Secured to the lower end of the tubing string l9, by a coupling 26, is a well pump 21, which comprises a pump barrel 23 having a standing valve assembly in the lower end thereof This assembly consists of a transverse plate 29 having a valve seat 35 therein, an upwardly opening ball valve 3! and a perforate baffle plate 32.

Afiixed to the lower end of the string of sucker rods 2! and mounted for sliding movement within the pump barrel 28 is a hollow pump plunger 33 equipped with a traveling valve assembly. The plunger 33 is provided with a passage or orifice 34 opening to the space within the pump barrel 28 below the plunger and forming a valve seat for an upwardly opening ball valve 35. The plunger 33 is also equipped with outlet ports 36 in communication with the space inside the pump barrel above the plunger. The lower end of the pump barrel 28 may be closed by a transverse plate member 31.

The plate member or coupling 31 may bethreaded to receive and secure a barrel extension or tubular member 38 coaxial with said pump barrel 28 having perforations or fluid ports 39 therethrough. One or more similar perforations 40 through the wall of the pump barrel 28, near its upper end, serve as discharge ports from the p mp.

Coaxially surrounding the pump barrel 28 and spaced therefrom is a tubular member 4| extending from a point above the discharge ports 40 to a point below the perforations 39 in member 38. The ends of said member 4| are swaged so as to be closed against the pump barrel 28 and barrel extension 38 as at 42 and 43, respectively, said closure being made fluid-tight in any suitable manner, as by welding. Thus, the surrounding tubular member 4| forms an annular space 44 between said member 4| and the pump barrel 28, said annular space 44 forming conduit means between fluid ports 39 and 40.

The pump is provided with one or more fluid intake ports 45 which are formed of short tubular pieces 46 extending in a fluid-tight manner through the walls of said barrel 28 and surrounding tubular member 4|, whereby the space Within the pump barrel 28 below the standing valve 3| is in communication with the space outside the tubular member 4|.

Carried on the outside of the pump below the inlet ports 45 thereof, either on the tubular member 4| or on the barrel extension 38, as shown, is a suitable packer means 4?. Since the structure and operation of the packer means form no part of this invention and are well known in the art, they will not be described here in detail.

In flooding operations, the present pump is secured to the lower end of the tubing string i9 and lowered into a well borehole or well casing to a position between an upper water-bearing sand it and a lower oil-bearing sand 48. Previously, the casing II and the surrounding layer of cement l! adjacent the water-bearing layer I6 is perforated at 53 by any suitable device such as a casing perforating gun. The packer 4? carried by the pump 27, or tubing 38 depending therefrom, is then expanded to seal off the annular space 49 between the pump 2? and the casing Water from the water-bearing sand it flows through the perforations 50 in the cement sheath ll and casing II to fill said annular space 49.

In the operation of the pump 21, the reciprocating motion of the sucker rod string 2! causes the hollow plunger 33 to move slidingly up and down within the pump barrel 28. On the upstroke of the plunger 33, water is drawn in the pump intake 45, and through the perforate plates 29 and 32 into the pump barrel 28 above the open standing valve 3| At the same time fluid standing above the closed traveling valve is forced up the barrel 28, out the perforations 40, down the annular conduit 4| and through 39 and tu- 4 bular member 38 to be discharged into the well casing below the packer 4'! and thence into the oil-bearing formation 48.

On the downstroke of the plunger 33, the standing valve 3| closes and the fluid in the pump barrel 28 between the standing valve 3| and traveling valve 35 is forced through perforations 34 and 36 into the pump barrel 28 above said traveling valve 35. From the above-described operation it may be seen that all fluid flowing from the water-bearing sand l6 and accumulating between the casing and pump 21 above the packer 41, may be forced under any desired pump pressure into the oil-bearing sand 48 to drive the oil therein to adjacent oil-producing wells. The flow of fluid from the water-bearing sand 16 to the oil-bearing sand 48 may be readily controlled by the rate at which the pump 21 is reciprocated.

Although the operation of the present pumping system has been described with reference to an upper water layer and a lower petroleum producing layer, it is understood that with suitable modifications it can equally well and without departing from the spirit of the invention be ap plied to any other geometrical configuration of formation layers.

We claim as our invention:

A well pump adapted to be installed on a tubular string member in a well to apply auxiliary pressure to a fluid being transferred from an upper relatively low-pressure formation to a lower relatively high-pressure formation, said pump comprising a pump barrel co-axial with said tubular string member, said tubular string member having upper and lower closure means above and below said pump barrel, a standing valve in said barrel, a traveling valve mounted for reciprocation in said barrel above said standing valve, a cylindrical housing closed at the top and bottom disposed around said barrel in spaced coaxial relationship therewith, port means through the walls of said barrel above the traveling valve opening to the space within said housing, port means in said tubular member below said lower closure means opening to the space within said housing, and conduit means extending radially through said housing, said conduit means opening at their outer ends to the space outside said housing and at their inner ends to said barrel below said standing valve and above said lower closure means.

JAMES EARLE GRAY. ELDON ALLEN DAVENPORT.

REFERENCES CITED UNITED STATES PATENTS Name Date Niles Sept. 10, 1940 Number 

